Refactoring.

Author: And1sS

src/main/java/org/prebid/server/auction/model/EidPermissionHolder.java

@@ -1,6 +1,7 @@
 package org.prebid.server.auction.model;
 
 import com.iab.openrtb.request.Eid;
+import org.apache.commons.collections4.CollectionUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.prebid.server.proto.openrtb.ext.request.ExtRequestPrebidDataEidPermissions;
 
@@ -49,7 +50,8 @@ public boolean isAllowed(Eid eid, String bidder) {
     }
 
     private int getRuleSpecificity(ExtRequestPrebidDataEidPermissions eidPermission) {
-        return (int) Stream.of(eidPermission.getInserter(),
+        return (int) Stream.of(
+                        eidPermission.getInserter(),
                         eidPermission.getSource(),
                         eidPermission.getMatcher(),
                         eidPermission.getMm())
@@ -65,7 +67,7 @@ private boolean isRuleMatched(Eid eid, ExtRequestPrebidDataEidPermissions eidPer
     }
 
     private boolean isBidderAllowed(String bidder, List<String> ruleBidders) {
-        return ruleBidders == null || ruleBidders.stream()
+        return CollectionUtils.emptyIfNull(ruleBidders).stream()
                 .anyMatch(allowedBidder -> StringUtils.equalsIgnoreCase(allowedBidder, bidder)
                         || WILDCARD_BIDDER.equals(allowedBidder));
     }

src/main/java/org/prebid/server/validation/RequestValidator.java

@@ -376,7 +376,7 @@ private void validateEidPermissions(List<ExtRequestPrebidDataEidPermissions> eid
                                         boolean isDebugEnabled,
                                         List<String> warnings) throws ValidationException {
 
-        if (ObjectUtils.isEmpty(eidPermissions)) {
+        if (CollectionUtils.isEmpty(eidPermissions)) {
             return;
         }
 
@@ -385,10 +385,12 @@ private void validateEidPermissions(List<ExtRequestPrebidDataEidPermissions> eid
                 throw new ValidationException("request.ext.prebid.data.eidpermissions[i] can't be null");
             }
 
-            validateEidPermissionCriteria(eidPermission.getInserter(),
+            validateEidPermissionCriteria(
+                    eidPermission.getInserter(),
                     eidPermission.getSource(),
                     eidPermission.getMatcher(),
                     eidPermission.getMm());
+
             validateEidPermissionBidders(eidPermission.getBidders(), aliases, isDebugEnabled, warnings);
         }
     }
@@ -397,10 +399,8 @@ private void validateEidPermissionCriteria(String inserter,
                                                String source,
                                                String matcher,
                                                Integer mm) throws ValidationException {
-        if (StringUtils.isEmpty(inserter)
-                && StringUtils.isEmpty(source)
-                && StringUtils.isEmpty(matcher)
-                && mm == null) {
+
+        if (StringUtils.isAllEmpty(inserter, source, matcher) && mm == null) {
             throw new ValidationException("Missing required parameter(s) in request.ext.prebid.data.eidPermissions[]. "
                     + "Either one or a combination of inserter, source, matcher, or mm should be defined.");
         }